An electrospray ionization ion mobility spectrometer (ESI-IMS) is proposed to be used as an innovative process analytical technology (PAT) to overcome the limitations of current cleaning validation systems for pharmaceutical manufacturing and quality assurance. With its sensitivity, speed and portability, IMS has already been used in trace chemical detection that includes cleaning validation applications in pharmaceutical manufacturing processes. However, current commercially available IMS systems have significant limitations in quantitative measurements and in the ability to analyze semi-volatile and non-volatile samples. In this project, an IMS is proposed to be interfaced to a novel electrospray ionization source for on-site analysis of both small molecule and biological pharmaceuticals. The new system will accept samples either directly from a swab or extracted sample solution. As these samples are introduced into the IMS, the targeted analytes are ionized, separated, and quantitatively detected within seconds. More importantly, the new IMS system allows detection of low charge affinity compounds and provides quantitative information of targeted active ingredients and other substance of interests. This on-site analytical technology can significantly reduce manufacturing down time and associated costs in the pharmaceutical manufacturing industry. PUBLIC HEALTH RELEVANCE: The proposed electrospray ionization ion mobility spectrometry (ESI-IMS) based cleaning validation technology is consistent with NIH's Process Analytical Technology (PAT) initiative, the goal of which is to improve efficiency in pharmaceutical manufacturing and quality assurance. This on-site analytical technology can significantly reduce manufacturing down time and associated costs in the pharmaceutical manufacturing industry, and could help lead to lower pharmaceutical costs to the public. Compared to existing IMS based cleaning validation methods, the proposed innovative IMS device fundamentally improves ion mobility spectrometry performance and enables direct introduction of swabbed samples, superior quantitative measurements, and the analysis of non-volatile and biological samples.